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tips for setting chevy head up on mill to cut guides?

Savedbygrace77

Aluminum
Joined
Jul 15, 2018
hi - im toying around with a junk head and would like to try test doing a valve guide.

I believe the chevy heads are 23 degrees, whats are some tips to getting the guide straight to the head? a tilting vise? I do have tapered pilots I can use to fine a faily decent center- just not sure how to deal with the angle..

Thanks
 
Look up seat and valve guide machines. The head mounting fixtures are not to complicated. They need to be robust so don't skimp on material. There were fixtures made for BP's and clones for head work. Any competent machinist could make one. To go to the trouble making one for commercial work on a mill is a lost cause. There isn't enough return on standard valve jobs.
How ever if you just want to because? A hobby project maybe go for it. Enjoy making one.
 
I was selling a #3 size horizontal / vertical milling machine on FB.
Really big machine, close to 6000 lbs. This guy messaged me
and wanted to use it to do valve guides and seats. I told him to
buy a Serdi machine instead. He got pissed and asked why I
think he could not do valves on the machine I was selling. This
because he wanted to mill heads and whatever, many trick pony.
I repeated this machine was not the machine for his application
and to buy some thing else. He kept bugging me to sell it to him.
Crazy. I ended up selling it to a young guy who had a job
rebuilding jet engines for Boeing. Seemed like a straight up guy
who actually knew about using the machine. But you get people
with big ideas who have never fully vetted them out, but yet
insist they know the best way. You'll have that on your larger jobs.
Not saying you can't do whatever. It is just that people are not
practical with the time and effort involved to do something the
hard way. Knowing this is called wisdom.

-Doozer
 
Bill has been an inspiration to us all for decades, however used head shop machines, with the necessary tooling, are so thick on the ground, building one's own is not cost-effective if one could be making more money doing something else.

Then, there's shop floor space. I know a Brit who builds engines in what we'd consider a closet. He does seats, guides, surfacing, boring, honing and balancing all on a knee mill.

jack vines
 
Having the right tooling for the job is definitely the way to go if doing this type of work for money. You're obviously not going to beat a machine that's sitting, set up and ready to go with job specific tooling and fixtures by using a turret mill with no specialized tooling to do the job. Bill's setup is pretty good in terms of adjustability and rigidity, but he's still got to get it setup and dialed in, which is time lost compared to a head specific machine that is always ready and waiting. Unless, of course, that's all he uses that specific mill to do.
 
Starting at 14:40 in this video,
You can get a very good look at his "floating table" with the adjustable angle plate he mounts the head on. This is all made up using some sort of heavy-duty drill press. I realize it's more than that and this is designed and built strictly for doing head work.
The point is, it would be very easy to build a simple "floating table" using linear rails, the ball type, to build with. The angular table part of it is simply a cradle arrangement with supports on each end. But you also have to note that cradle, the flat table part of it is actually two short pieces the mount on the ends of the head. These are changed according to the head style used. Just saying.
 
Everything said above is true, and there is a glut of special purpose engine machinery. A 10x15" tilting table works well for head work on a knee mill. A 90 deg angle plate is also useful for some setups.
 
For a small block Chevy no special fixture is necessary. Use a couple of angle plates bolted to the ends of the head to tilt the head so the valves are roughly vertical. Now install a pilot in the valve guide of the desired valve. Now tram the head to the pilot, both swing and nod. It will take a little while to get the feel for how much to move the head each time, but with a little practice it will only take a couple of minutes per valve.
 
hi - im toying around with a junk head and would like to try test doing a valve guide.

I believe the chevy heads are 23 degrees, whats are some tips to getting the guide straight to the head? a tilting vise? I do have tapered pilots I can use to fine a faily decent center- just not sure how to deal with the angle..

Thanks
This guy seems to know his onions. Lots of head work with limited tools, plenty of method talk with more than a side of sarcasm.
 








 
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